Overview
Even the most powerful furnace
can’t do its job without proper insulation and air sealing. Even the coldest AC
unit needs a well-insulated area to cool you off on a warm day. Get more out of
your heating and cooling and conserve energy with proper insulation and air
sealing. Unless your home is brand new - and built by a knowledgeable
contractor - you can probably add insulation for a major boost on your home’s
energy efficiency.
Home Insulation for your Attic, Basement and Walls
The optimal amount of insulation - whether
it’s blown, batt or spray foam insulation - varies according to local climate and
the part of the house being insulated (attic, walls or basement).
Do-it-yourself insulation and air sealing is difficult to get right: Incomplete
coverage and improper air-sealing can seriously compromise the effectiveness of
insulation. It may look easy, but unless you’re trained in building science and
happy to crawl around in the dust and grime of the furthest reaches of your
attic and crawlspace, it’s almost always best to bring in a professional. A
professional contractor can determine the optimal amount of insulation
depending on your location.
First Step: Attic Insulation
If you have to choose one area
for home insulation, choose the attic. Attic insulation is one of the most
important and cost-effective projects to get right in your home for optimal
comfort and energy efficiency, regardless of local climate. The attic is
relatively easy to access and is subject to extreme temperature swings in the
winter and summer. For more information on attic insulation, click here.
Exterior Wall Insulation
An exterior wall is any wall
that faces outside or otherwise separates your home from the outdoors
(including basement walls). These walls should be insulated to create a thermal
envelope around your living space. This also includes “knee walls”, which are
walls that face an unconditioned indoor space like your attic or garage.
Air Sealing a Cold, Drafty House
Proper air sealing is among the
most cost-effective strategies for conserving energy around your home. Protect
your home from harsh outdoor temperatures with professionally installed air
sealing. Qualified professionals will know that a certain amount of ventilation
is necessary to keep air moving.
Unless your house was built in
the last five to ten years, there are probably major air leaks in the living
space and in the building shell. Older homes can be extremely leaky, which
means the hot or cold air that your heater or air conditioner puts out is mostly
blowing out of the house. If an older home is sealed too tightly, a mechanical
ventilation system - sometimes called an Energy Recovery Ventilator - may be needed
to ensure healthy air quality.
After completing an online
audit, the first step is to get an in-home energy audit to determine how much
air leakage your home currently has and how much of that leakage can be sealed
safely to maximize your utility bill savings and minimize your carbon
footprint.
Testing to Reveal Air Leaks
A blower door test is commonly
used to determine where any air is leaking in and out of your home. The blower
door test starts by depressurizing your home - contractors insert a door with a
built in fan that will blow air out your entryway. As the air inside your home
is pushed outside through the front door, air from outside of your home will
start to seep in through any cracks.
Auditors use colored smoke to make the moving air visible. They will
note the areas where air is seeping in during the blower door test so they can
come back and seal them up later using foam, caulk or other sealants. The most
common problem areas are found on exterior walls or walls that connect to
garages, as well as ceilings and floors connecting to attics and crawlspaces.
The windows, chimneys, vents, recess lights, attic hatches, electrical outlets
and outdoor faucets found on these exterior walls are often high-leakage areas
that can be sealed easily. It’s also important to note that air sealing and
insulation go hand in hand. If you plan to add insulation to improve the
efficiency of your house, be sure to talk with a professional about air sealing
at the same time. Without air sealing, your new insulation may be much less
effective.
Air Seal and Insulate Your Ducts
If you’ve got a forced air
heating or air conditioning system, duct sealing and insulation can
significantly reduce your energy consumption. Most homes with unsealed,
insulated ducts lose between 10 to 30 percent of the energy used for heating
and cooling because the nice warm (or cold) air in their air ducts leaks out
before it reaches the living space. In other words, almost a third of what
you’re paying to heat or cool your home is wasted before it ever gets to you.
Don’t forget the return ducts as
well – many times, return ducts are built into walls. If they are pulling air
from outside the home, your furnace and air conditioner’s effectiveness will
suffer from any leakage. You’ve got to be careful to seal every junction and
seam where there’s leakage - otherwise, the air will just leak out even faster
from spots you missed.
Add duct insulation, made of
foil or vinyl, after the duct sealing is complete. If you’d like to find a professional who can
help do this for you, we can help you find an expert in your area or check out
the Building Performance Institute (BPI) directory of energy efficiency
specialists in your area.
Ready to start your project?
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